Abstract
Carbon dioxide sequestration via carbonation of steel slags is a promising way of combining two waste products to create value. Understanding the dissolution kinetics of steel slags, which are alkaline and rich in calcium, in acidic media is essential to configure such a process. In this study, we seek to analyse the dissolution mechanism from experimental studies and develop a mathematical model considering the heterogeneous characteristics of slag. We found that the reduction in calcium extraction efficiency with an increase in particle size, which is normally associated with surface passivation or non-uniformity of samples, can be explained by considering the morphological features associated with the distribution of MgO-FeO (RO) phase in the calcium silicate matrix. We present a population balance model and show that the reduction in calcium extraction efficiency in coarse particle fractions is due to increased sporulation of the RO phase. The findings in the study suggest that the leaching of metal ions from slag is controlled by proton-promoted surface dissolution reaction, where the dependence of acid concentration follows the Langmuir-Hinshelwood adsorption isotherm. The model shows good agreement with a large set of parametric studies and demonstrates the importance of considering morphological features, as we progress towards development of a priori dissolution models for multi-mineral oxides and silicates.
| Original language | English |
|---|---|
| Article number | 20180830 |
| Number of pages | 20 |
| Journal | Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences |
| Volume | 475 |
| Issue number | 2224 |
| DOIs | |
| Publication status | Published - 1 Jan 2019 |
Keywords
- Calcium selectivity
- Mineral carbonation
- Population balance modelling
- Sporulation
- Surface area
Cite this
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Kinetics of steel slag dissolution : from experiments to modelling. / Ragipani, Raghavendra; Bhattacharya, Sankar; Suresh, Akkihebbal K.
In: Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 475, No. 2224, 20180830, 01.01.2019.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - Kinetics of steel slag dissolution
T2 - from experiments to modelling
AU - Ragipani, Raghavendra
AU - Bhattacharya, Sankar
AU - Suresh, Akkihebbal K.
PY - 2019/1/1
Y1 - 2019/1/1
N2 - Carbon dioxide sequestration via carbonation of steel slags is a promising way of combining two waste products to create value. Understanding the dissolution kinetics of steel slags, which are alkaline and rich in calcium, in acidic media is essential to configure such a process. In this study, we seek to analyse the dissolution mechanism from experimental studies and develop a mathematical model considering the heterogeneous characteristics of slag. We found that the reduction in calcium extraction efficiency with an increase in particle size, which is normally associated with surface passivation or non-uniformity of samples, can be explained by considering the morphological features associated with the distribution of MgO-FeO (RO) phase in the calcium silicate matrix. We present a population balance model and show that the reduction in calcium extraction efficiency in coarse particle fractions is due to increased sporulation of the RO phase. The findings in the study suggest that the leaching of metal ions from slag is controlled by proton-promoted surface dissolution reaction, where the dependence of acid concentration follows the Langmuir-Hinshelwood adsorption isotherm. The model shows good agreement with a large set of parametric studies and demonstrates the importance of considering morphological features, as we progress towards development of a priori dissolution models for multi-mineral oxides and silicates.
AB - Carbon dioxide sequestration via carbonation of steel slags is a promising way of combining two waste products to create value. Understanding the dissolution kinetics of steel slags, which are alkaline and rich in calcium, in acidic media is essential to configure such a process. In this study, we seek to analyse the dissolution mechanism from experimental studies and develop a mathematical model considering the heterogeneous characteristics of slag. We found that the reduction in calcium extraction efficiency with an increase in particle size, which is normally associated with surface passivation or non-uniformity of samples, can be explained by considering the morphological features associated with the distribution of MgO-FeO (RO) phase in the calcium silicate matrix. We present a population balance model and show that the reduction in calcium extraction efficiency in coarse particle fractions is due to increased sporulation of the RO phase. The findings in the study suggest that the leaching of metal ions from slag is controlled by proton-promoted surface dissolution reaction, where the dependence of acid concentration follows the Langmuir-Hinshelwood adsorption isotherm. The model shows good agreement with a large set of parametric studies and demonstrates the importance of considering morphological features, as we progress towards development of a priori dissolution models for multi-mineral oxides and silicates.
KW - Calcium selectivity
KW - Mineral carbonation
KW - Population balance modelling
KW - Sporulation
KW - Surface area
UR - http://www.scopus.com/inward/record.url?scp=85065421487&partnerID=8YFLogxK
U2 - 10.1098/rspa.2018.0830
DO - 10.1098/rspa.2018.0830
M3 - Article
C2 - 31105457
AN - SCOPUS:85065421487
VL - 475
JO - Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
JF - Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
SN - 1364-5021
IS - 2224
M1 - 20180830
ER -